LinuxQuestions.org - generic or huge kernels?

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generic or huge kernels?

For first...I'm not making this topic to flame, I'm making this topic because I've seen many topics where people flamed to choose these kernels, now...Which kernel is most used between *generic and *huge? For first I give my personal opinion:

Actually I use the generic kernel for two reasons:

-Pat suggests it.
-It's slim.

but I've always used the huge kernel. Now, in the using of the generic kernel I had to type one command to make the "initrd.gz" and I had to edit the lilo.conf(the guide is wrote in the /boot/README.initrd). No,w it works perfectly. Now the question is:

"Which kernel do you use"? "Why do you use it?"

I use the generic. I was under the impression the 'huge' kernel was only intended as a bootstrap kernel and isn't recommended for normal use.

Hi,

I thought the suggestion was to use hugesmp kernel. This is the one I use.
In the begginning, when I first installed slackware, I used the generic kernel...by accident. I am using the GRUB from another distro to boot the various OSes so I added an entry there for slackware and since I did not know at the beggining which kernel to use I just picked up generic. But then I think I read somewhere that it is the hugesmp that is recommended so I changed it. Nevertheless I am not noticing any difference till now, or the use I am making of my system does not reveal any difference.

Quote:

Originally Posted by GazL (Post 3507107)

I use the generic. I was under the impression the 'huge' kernel was only intended as a bootstrap kernel and isn't recommended for normal use.

You are correct sir :)

mRgOBLIN

Quote:

You are correct sir

As a Slackware contributor, perhaps you could explain why you should not use the hugesmp kernel as, after all is said and done, it does work on a day to day basis.

samac

I compile my own kernel, based on the config from the generic-smp kernel supplied by Slackware.
I build in some modules so I don't need an 'initrd' and change some parameters needed for my hardware.

But basically it is the generic kernel with some fine-tuning in the configuration.

Hi,

I prefer to use 'PV's' definition;

Quote:

excerpt from CHANGES_AND_HINTS.TXT;
As stated earlier, it is recommended that you use one of the generic kernels
rather than the huge kernels; the huge kernels are primarily intended as
"installer" and "emergency" kernels in case you forget to make an initrd.
For most systems, you should use the generic SMP kernel if it will run,
even if your system is not SMP-capable. Some newer hardware needs the
local APIC enabled in the SMP kernel, and theoretically there should not be
a performance penalty with using the SMP-capable kernel on a uniprocessor
machine, as the SMP kernel tests for this and makes necessary adjustments.
Furthermore, the kernel sources shipped with Slackware are configured for
SMP usage, so you won't have to modify those to build external modules
(such as NVidia or ATI proprietary drivers) if you use the SMP kernel.

If you decide to use one of the non-SMP kernels, you will need to follow the
instructions in /extra/linux-2.6.27.7-nosmp-sdk/README.TXT to modify your
kernel sources for non-SMP usage. Note that this only applies if you are
using the Slackware-provided non-SMP kernel - if you build a custom kernel,
the symlinks at /lib/modules/$(uname -r)/{build,source} will point to the
correct kernel source so long as you don't (re)move it.

To date I have not had any issues that would require the use of the installer kernels other than as a recovery kernel with the install cd.

Generic, because I sometimes do as I am told.

I used to compile my own kernels, but have started using the stock kernels instead. It is just too easy to copy a kernel from one machine to another, without worrying about how it was customized. I'm currently using four machines on this network & have the same kernels on all four. I have both huge & generic kernels installed (in case I need to boot from the huge one after one of my "mistakes"), have gotten rid of the "vmlinuz" link & use "huge" & "generic" links instead. So, I don't have to remember the exact kernel name. It's easy enough to modify the stock generic kernel to contain your filesystem drivers, so that an initrd will not be necessary, but I have modified the mkinitrd package so that I can boot with "root=LABEL=whatever" or "root=UUID=whatever" & that requires an initrd anyway, so I just leave the kernel alone.
Regards,
Bill

I leave the "vmlinuz" link alone, as it always comes back after an update of the kernel from -current or a new release.

The generic and -custom (compiled kernel) I add to the lilo menu, with the -custom as a default. The huge kernel stays there, in case I mess up something, so I don't need to find a bootable CD.

As others have said - I always use generic because the Slackware creator says to - never had any problems.

Again - always leave a boot option for hugesmp.s in case of problems creating initrd or whatever.

Quote:

Originally Posted by bgeddy (Post 3507611)

Always leave a boot option for hugesmp.s in case of problems creating initrd or whatever.

Yes, once you're sure everything works OK. Like this:

Code:

# Linux bootable partition config begins

image = /boot/vmlinuz-generic-smp-2.6.27.7-smp

  initrd = /boot/initrd.gz

  root = /dev/sda1

  label = Linux_G

  read-only

# Linux bootable partition config ends

# Linux bootable partition config begins

image = /boot/vmlinuz

  root = /dev/sda1

  label = Linux_H

  read-only

# Linux bootable partition config ends

I'm still at a loss. PV says that we should use the generic kernel, but it seems that we have to take this on faith, why should we not use the hugesmp.s kernel?

Just to clarify, I am using the generic kernel, I would just like to know for curiosities sake.

samac

One reason I can think of: troubleshooting.

The huge kernel loads about everything in memory - many things you'll never use. If anything goes wrong (panic, oops), it will be (more) difficult to say why.

Yes - to me it makes more sense to load modules as and when needed,(in theory), rather than have the world built into and loaded from one monolithic kernel. The monolithic may be beneficial to get the majority of machines going but unnecessary for daily use.